An LCD device includes a display module which generally employs a backlight to provide a light source for displaying of images. Conventional backlight sources mainly include CCFL and LED. At present, as a novel light source, LED has the advantages of high brightness and low power consumption. Thus, the design of LED backlights is increasing and has become a trend in the future. However, LED generates high heat. To ensure the light-emitting efficiency and the service life of LED, it is necessary to improve the heat dissipation capacity of LED.
Now, heat dissipation mainly includes backplane heat dissipation and aluminum extrusion (aluminum extrusion type heat dissipation section) heat dissipation. The backplane heat dissipation requires the whole backplane to be made of aluminum or an aluminum alloy, resulting in high cost, which does not accord with the low-cost design requirement and thus is not widely used. As shown in FIG. 1, the aluminum extrusion heat dissipation refers to the manner that an LED light source 1 is fixed on an aluminum extrusion 2, and the aluminum extrusion 2 is mainly used for heat dissipation. The backplane can be made of SECC steel plates or plastic. However, with regard to the heat dissipation structure, the aluminum extrusion 2 is arranged inside the backplane 3, and the contact area between the aluminum extrusion and air is small, especially the contact area between the aluminum extrusion and the outside flowing air is small, thus, the heat dissipation efficiency cannot be increased.